Piano-plate for upright pianos.



U. MEHLIN.

PIANO PLATE FOE UPRIGHT PIANOS.

APPLICATION FILED JANA, 1913.

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WITNESSES INVENTUH UNITED STATES PATEN T ()FFICE,

CHARLES MEHLIN, OF FORT LEE, NEW J ERSEYf PIANO-PLATE FOR UPRIGHT PIANOS.

Specification of Letters laten't;

To all whom it concern Be 1t known that I, CHARLES MEHLIN, a

citizen of the United States, residing in Fort,

Lee, Bergencounty, State of New Jersey, have invented certain new and useful Improvements in Piano-Plates for Upright Pianos, of which the following is a specification, reference being had ,to the accompanying dyawings, which form a part hereof.

This invention relates to piano plates for upright pianos and has for an object to im;

prove the construction thereof, so as to strengthen the same and at the same time permit that degree of resiliency which isessential to insure full and clear tones.

A further object is to so dispose the bars of the plate on which the strain 'of the strings falls with respect to the strings, that the sound waves set up by the vibrations of 20,,thelatter shall not be interfered with by the thereof.

bars. In previous constructions it has been deemed necessary to place "a bar parallel with and close to the bass stri strain thereof, as "well as to resist the strain of the middle strings. It has been found, however, that a bar or rib so disposed, interferes with the vibration of the adjacent bass strings and steel strings and makes the plate too rigid for a good tone effect, depriving it of a degree of resiliency which is found to be desirable, as indicated above. Then too, a bar thus disposed'interfe'res with the ready insertion or removal of the middle strings, which lie beneath the bass strings and also pass beneath the bar.

Therefore, it is a further object of this invention to dispose this strengthening bar entirely apart from the middle strings so that free access may be had to the latter. In accordance with the invention the usual strengthening bar for the bass stringsl'ias its upper end in relatively the same position as before but has its lower end carried away from the lower ends of the bass strings so that the bar is out of parallelism therewith, and is attached to thestring plate at a point adjacent the corresponding lower corner In this position the bar has a greater angularity with respect to the bass strings but a lesser angularity with respect 'to the middle strings, the effect being to strengthen the entire frame and improve the sounding qualities of the board.

The invention will be more particularly s to takethe describedhereinafterwith respect to the accompanying drawings in which Figure 1 is a View in elevation of the improved plat-e. showing the relative positions of the new bar to the'bass strings and middle strings. Fig. 2 is a view in section taken on the. plane indicated by the line 22 of Big. 1, the strings being omitted.

The string plate a may be formed of-fauy approved outline and have the usual open sounding, qualities to that. extent ,to which such. features affect the sounding qualities. The treble strings a; middle strings I} and bass strings 6 may be secured at their ends to hitch pins f set in the plate, in the manner well known and now'in general use. General rigidity of the string plate a may be secured as usual, by bars 9 and in connecting the upper and lower sections of the piano plate and suitably disposed with respect to the treble and middle strings respectively so as to absorb directly to a degree, the strain thereof. The description thus far given relates to the usual construction of piano plates and to features which will enable a better understanding of the present inven tion but with which the improvements herein claimed, arej not directly concerned. As is usual in most approved forms of piano plates the middle strings 0? lie under the bass strings e and are angularly disposed thereto. It will be noted that the strain imposed on the piano plate by the two sets of strings is generally in the same direction and so it is necessary to provide the plate a with a rib or bar so disposed with respect thereto as to take up the major portion of suchstrain.-'

Patented Mar. 17, 1914. Application filed January 4, 1913 Serial No. (40,114.

portions-"Zr therein to procure the. desired,x

In previous constructions it has been thought necessary to dispose such a bar parallel to and in juxtaposition to the bass strings and extending from the top to the bottom of the:

piano plate. It has been found, however,

that this bar deadens the vibrations of the adjacent bass strings and so reinforces the piano plate as to form a structure entirely too rigid for the most desirable tone effects.

' Such a bar, it will be understood, necessarily lies over the middle strings so that it isv impossible to insert or remove the same readily from the piano plate owing to the interference of the strengthening bar.

In accordance with the present invention the bar above referred to, herein designated by the. reference character 6, lies wholly without the zone of the bass strings and has its upper end 2" preferably united integrally with the piano-plate and has its lower end 2' carried away from the lower ends of the bass strings e to the corresponding lower end or corner of the piano plate, with which it has preferably an integral union. At a suitable point intermediate the ends of thebar i and extending between the latter and the bar it, or its equivalent, is disposed a transverse reinforc ng rib i The function of such a rib, in resisting lateral strains imposed on the bar 2' and the other portion of the piano plate to which it is attached, will be readily appreciated. The arrangement of the bar therein disclosed, places the same in a substantially vertical position so that its angularity with respect to the middle strings (Z is decreased and its effective support of said strings correspondingly increased. The angularity with respect'to the bass strings e is, of course, increased but it has been found that such a relationship as herein disclosed is highly desirable since it permits that degree of resiliency of the frame which is necessary to secure good tone effects from the vibrations of these bass strings. Then too, it is obvious that the sound waves of the proximate bass strings e are not interfered with as in the previous constructions hereinbefore referred to; It will also be observed that the bar '5 no longer lies over the middle strings d, so that their insertion or removal may be readily effected. Likewise, the sound waves produced by these middle strings are not interfered with by the bar 2' and a clearer tone results from the construction herein employed. It will be noted that by disposing the bar Z in the position illustrated in the accompanying drawings the openings 6 of the string plate, by reason of which the sounding board is operative, are not crossed or partially cut off. Superior tone elfects are therebysecured. Again it will be clearly seen that by placing the bar a" as shown instead of placing it parallel to the bass strings e, which is the usual form of construction, an open and unbridged space is obtained, that is, as far as the middle and bass strings are concerned, causing neeaeze no interference with the sound waves nor with the resiliency of the plate, which interference has always been apparent in the previous forms of construction of stringed plates for upright pianos. lt will therefore be clearly seen that the disposition of the bars in the present form of construction produces a plate that is highly resilient and therefore permits the use of thinner strings, which of course permit a lower tensile strain than thicker ones,and necessarily produce a note of better singing quality.

What I claim is:

1. A string plate for over-strung upright pianos, comprising an upper, lower, and side portions, and two intermediate brace-bars only, said bars extending between the upper and lower portions and disposed at the opposite sides of the middle strings, one of said bars being parallel to the treble strings and shorter side portion, and the other said bar being substantially parallel to the middle strings and at a considerable angle to the other side portion, the space between the two said bars being open and unbridged, and means for attaching the over-strung strings at an angle to the second side per-- tion.

2. A string plate for over-strung upright pianos, comprising an upper, lower, and side portions, and two intermediate brace here only, said bars extending between the upper and lower portions and disposed at the opposite sides of the middle strings, one of said bars being parallel to the treble strings and shorter side portion, and the other said bar being substantially parallel to the middle strings and at a considerable angle to the other side portion, the space between the two said bars being open and unbridged, means for attaching the over strung strings at an angle to the second side portion, and a transverse bar extending between said second side portion and the adjacent brace bar.

This specification signed and witnessed this 28th day of December, A. D. 1912.

. ennnnns Mantra Copies of this patent may be obtained for five cents each, by addressing the Goramissioner of irritants;

Washington, D. G. 

